This invention relates to self-gripping devices containing dynamic self-gripping elements which are capable of entering into reversible self-gripping engagement with fibrous or porous receiving materials and which offer a great degree of protection from damage upon forming and dissociating the self-gripping junction.
This invention also relates to gripping elements having unique self-gripping means.
Self-gripping devices have been known for some time but only recently have they begun to replace conventional fastening devices such as staples, snaps, nails, adhesives and the like. In general, self-gripping devices perform many unique functions which conventional fasteners cannot provide. For instance, there is unlimited freedom of self-gripping engagement over an area by virtue of the vast number of gripping sites in a receiving material. This has the effect of eliminating alignment criticalities that seriously hamper conventional fasteners, involving mating specific fastening sites such as a bore or hole with corresponding fastening devices such as a screw, bolt, snap or rivet or the two halves of a zipper.
A reversible or permanent self-gripping connection can be formed simply by hand without the need for special tools. Once a reversible self-gripping connection is formed it can be pulled apart due to the releasable nature of the self-gripping connections. This may provide for invisible attachment that leaves no visible marks once the connection is pulled apart and established elsewhere on the surface. This is especially true for carpet covered walls and ceilings which are finding increased use as an interior surface finish.
Also, a plurality of gripping elements in a self-gripping device cooperate to provide the required amount of self-gripping holding force and distribute same over a predetermined area thus avoiding localized stress concentrations such as occurs with conventional fasteners.
Another desirable feature is that the gripping elements of a device may be inherently flexible which allows a self-gripping connection to accommodate dimensional changes caused by large thermal coefficients of expansion that occur between similar or dissimilar articles connected to each other by a self-gripping mechanism. This prevents buckling and cracking of joined articles.
One more capability of self-gripping devices is the ability to form a self-gripping connection between articles on any face, edge or corner by simply bringing any pair of these into contact at the desired location.
With the increasing use and advancing sophistication of self-gripping devices certain advantages and capabilities for special and unique applications become important. For example, in many instances it is desirable to form a self-gripping connection with a receiving material and especially fibrous receiving materials, without damaging or harming the receiving material. This becomes even more critical where it is desirable to form a reversible or releasable self-gripping engagement without causing any damage or leaving marks upon detaching the articles at the site of the formed self-gripping connection.